ABSTRACT Introduction The genus Moerckia Gottsche belongs to the order Pallaviciniales, the phylo... more ABSTRACT Introduction The genus Moerckia Gottsche belongs to the order Pallaviciniales, the phylogeny of which has been insufficiently studied. We re-evaluate the phylogenetic position of M. blyttii and the importance of certain morphological features, and re-emphasise the differences in morphology, ecology and distribution of M. hibernica and M. flotoviana. Methods DNA data from three nucleotide markers, namely ITS1 to ITS2 nrDNA, trnL–F and trnG intron cpDNA, were obtained from specimens of Moerckia species, including the generitype M. hibernica, which had not been sequenced before. Relationships were explored using maximum parsimony, maximum likelihood and Bayesian analyses. Key results In the results of molecular analyses, specimens of Moerckia hibernica from Ireland and Scotland formed a sister clade to that of M. flotoviana, and M. blyttii retained its distinct position basal to both Moerckiaceae and Pallaviciniaceae. This clarifies the phylogenetic position of M. hibernica as well as that of the Pallaviciniales as a whole. The most significant morphological characters to distinguish M. flotoviana from M. hibernica are placement of antheridial scales, width-to-length ratio of thallus segments, and width of midrib; conducting strands are a less important differentiating feature, being present in both species and often weakly developed. The results showed the variability and overlap of some morphological characters. Conclusion The new family Pseudomoerckiaceae and a new monotypic genus, Pseudomoerckia, created to accommodate Moerckia blyttii, are described. Cordaeaceae Mamontov et al. is synonymised with Moerckiaceae K.I.Goebel ex Stotler & Crand.-Stotl. The species status and restricted distribution of M. hibernica are confirmed.
Sibbaldia: the Journal of Botanic Garden Horticulture, 2017
The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet... more The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet and northern Myanmar seems to be one of the last frontiers not only for Meconopsis hunting but also for other botanical exploration. Although there remain political difficulties for foreigners to approach the unsettled border between India and China, including the famous Tsari valley with its prominently rich flora, which was visited by Frank Ludlow, George Sherriff, Frank Kingdon-Ward and a few other plant hunters before 1950, some botanical and horticultural treasures in this region have gradually been revealed to recent travellers. As a result of examining the photographs taken by these travellers and our own botanical field research in eastern Bhutan in 2014, accompanied by subsequent herbarium studies, two species new to science are described. The first, from eastern Bhutan and adjacent Arunachal Pradesh and Tibet, has long been cultivated under the names M. grandis or M. grandis G...
Sibbaldia: the International Journal of Botanic Garden Horticulture, 2017
The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet... more The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet and northern Myanmar seems to be one of the last frontiers not only for Meconopsis hunting but also for other botanical exploration. Although there remain political difficulties for foreigners to approach the unsettled border between India and China, including the famous Tsari valley with its prominently rich flora, which was visited by Frank Ludlow, George Sherriff, Frank Kingdon-Ward and a few other plant hunters before 1950, some botanical and horticultural treasures in this region have gradually been revealed to recent travellers. As a result of examining the photographs taken by these travellers and our own botanical field research in eastern Bhutan in 2014, accompaniedby subsequent herbarium studies, two species new to science are described. The first, from eastern Bhutan and adjacent Arunachal Pradesh and Tibet, has long been cultivated under the names M. grandis or M. grandis GS...
The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the... more The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the margins of the African continent and neighbouring oceanic archipelagos. Here, we tested whether the phylogeographical pattern of Exormotheca pustulosa Mitt. was the result of vicariance induced by past climatic changes or the outcome of a series of recent long-distance dispersal events. Two chloroplast markers (rps4-trnF region and psbA-trnH spacer) and one nuclear marker (ITS2) were analysed. Phylogenetic and phylogeographical relationships were inferred as well as divergence time estimates and ancestral areas. Exormotheca possibly originated in Eastern Africa during the Late Oligocene/Early Miocene while Exormotheca putulosa diversified during the Late Miocene. Three main E. pustulosa groups were found: the northern Macaronesia/Western Mediterranean, the South Africa/Saint Helena and the Cape Verde groups. The major splits among these groups occurred during the Late Miocene/Pliocene; ...
AimWe used published data of the floristic and elevational distribution of seed plants of Bhutan ... more AimWe used published data of the floristic and elevational distribution of seed plants of Bhutan to test the contribution of climatic, topographical and biogeographical variables to shape elevational species richness and endemism patterns.LocationBhutan.MethodsWe compiled data of seed plant species distributions from the Flora of Bhutan and related them to energy, humidity, and topographically related variables and biogeographical distributions. We used multiple regression models to identify most predictive independent variables by multi‐model‐inference based on AICc.ResultsWe find highest species richness at mid elevations (1500–2000 m), while endemic richness peaks markedly higher at 4500 m. Separated for life forms, the peak of richness shifts upward along the elevational gradient in the order of trees – shrubs – herbs – graminoids. Elevational richness peaks of temperate taxa were centred at high and of tropical taxa at low elevations. Temperature was identified as most influent...
Didymodon hengduanensis is described as a new species from the Hengduan Mountains in the province... more Didymodon hengduanensis is described as a new species from the Hengduan Mountains in the provinces of Sichuan and Yunnan, China. It is characterized mainly by its lanceolate to ovate-lanceolate and appressed-incurved leaves when dry, acute leaf apices, recurved to revolute margins, the yellowish color in KOH, percurrent to subpercurrent costa, and marginal basal cells forming a distinctly differentiated area of smooth and transversely thick-walled cells. Drawings and light microscope photographs of the new species are provided. The principal characters that separate it from the most similar species are discussed.
Ceylon Journal of Science (Biological Sciences), 2016
As part of a study initiated to trace the evolutionary relationships and biogeographic affinities... more As part of a study initiated to trace the evolutionary relationships and biogeographic affinities of Sri Lankan complex thalloid liverworts, we here present the morphological diversity of Sri Lankan complex thalloid liverworts. This serves as the first detailed taxonomic study of the group in Sri Lanka. Specimens were collected from different geographical regions covering almost all topographic and climatic zones of the country. This study revealed 9 genera of complex thalloid liverworts in Sri Lanka. Based on our collections and identifications we prepared a generic key to Sri Lankan complex thalloid liverworts. Taxonomic descriptions were prepared for all identified genera
The phylogenetic placement of Monocarpus sphaerocarpus D.J.Carr (Monocarpaceae), a member of the ... more The phylogenetic placement of Monocarpus sphaerocarpus D.J.Carr (Monocarpaceae), a member of the complex thalloid liverworts with highly specialised morphology, presumably related to its saltpan habitat, has been determined on the basis of molecular data. Within the complex thalloid liverworts, Monocarpus resolves as sister to the Sphaerocarpales clade. A new line drawing of Monocarpus is provided, as are the first colour photographs of living plants. Detailed ornamentation of the spores of Monocarpus collections from Australia and South Africa, as revealed by scanning electron micrography, is reported, and some of the morphological features that unite and separate Monocarpus and the Sphaerocarpales s.str. are discussed.
ABSTRACT Introduction The genus Moerckia Gottsche belongs to the order Pallaviciniales, the phylo... more ABSTRACT Introduction The genus Moerckia Gottsche belongs to the order Pallaviciniales, the phylogeny of which has been insufficiently studied. We re-evaluate the phylogenetic position of M. blyttii and the importance of certain morphological features, and re-emphasise the differences in morphology, ecology and distribution of M. hibernica and M. flotoviana. Methods DNA data from three nucleotide markers, namely ITS1 to ITS2 nrDNA, trnL–F and trnG intron cpDNA, were obtained from specimens of Moerckia species, including the generitype M. hibernica, which had not been sequenced before. Relationships were explored using maximum parsimony, maximum likelihood and Bayesian analyses. Key results In the results of molecular analyses, specimens of Moerckia hibernica from Ireland and Scotland formed a sister clade to that of M. flotoviana, and M. blyttii retained its distinct position basal to both Moerckiaceae and Pallaviciniaceae. This clarifies the phylogenetic position of M. hibernica as well as that of the Pallaviciniales as a whole. The most significant morphological characters to distinguish M. flotoviana from M. hibernica are placement of antheridial scales, width-to-length ratio of thallus segments, and width of midrib; conducting strands are a less important differentiating feature, being present in both species and often weakly developed. The results showed the variability and overlap of some morphological characters. Conclusion The new family Pseudomoerckiaceae and a new monotypic genus, Pseudomoerckia, created to accommodate Moerckia blyttii, are described. Cordaeaceae Mamontov et al. is synonymised with Moerckiaceae K.I.Goebel ex Stotler & Crand.-Stotl. The species status and restricted distribution of M. hibernica are confirmed.
Sibbaldia: the Journal of Botanic Garden Horticulture, 2017
The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet... more The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet and northern Myanmar seems to be one of the last frontiers not only for Meconopsis hunting but also for other botanical exploration. Although there remain political difficulties for foreigners to approach the unsettled border between India and China, including the famous Tsari valley with its prominently rich flora, which was visited by Frank Ludlow, George Sherriff, Frank Kingdon-Ward and a few other plant hunters before 1950, some botanical and horticultural treasures in this region have gradually been revealed to recent travellers. As a result of examining the photographs taken by these travellers and our own botanical field research in eastern Bhutan in 2014, accompanied by subsequent herbarium studies, two species new to science are described. The first, from eastern Bhutan and adjacent Arunachal Pradesh and Tibet, has long been cultivated under the names M. grandis or M. grandis G...
Sibbaldia: the International Journal of Botanic Garden Horticulture, 2017
The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet... more The region from eastern Bhutan to Arunachal Pradesh of India and the adjacent south-eastern Tibet and northern Myanmar seems to be one of the last frontiers not only for Meconopsis hunting but also for other botanical exploration. Although there remain political difficulties for foreigners to approach the unsettled border between India and China, including the famous Tsari valley with its prominently rich flora, which was visited by Frank Ludlow, George Sherriff, Frank Kingdon-Ward and a few other plant hunters before 1950, some botanical and horticultural treasures in this region have gradually been revealed to recent travellers. As a result of examining the photographs taken by these travellers and our own botanical field research in eastern Bhutan in 2014, accompaniedby subsequent herbarium studies, two species new to science are described. The first, from eastern Bhutan and adjacent Arunachal Pradesh and Tibet, has long been cultivated under the names M. grandis or M. grandis GS...
The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the... more The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the margins of the African continent and neighbouring oceanic archipelagos. Here, we tested whether the phylogeographical pattern of Exormotheca pustulosa Mitt. was the result of vicariance induced by past climatic changes or the outcome of a series of recent long-distance dispersal events. Two chloroplast markers (rps4-trnF region and psbA-trnH spacer) and one nuclear marker (ITS2) were analysed. Phylogenetic and phylogeographical relationships were inferred as well as divergence time estimates and ancestral areas. Exormotheca possibly originated in Eastern Africa during the Late Oligocene/Early Miocene while Exormotheca putulosa diversified during the Late Miocene. Three main E. pustulosa groups were found: the northern Macaronesia/Western Mediterranean, the South Africa/Saint Helena and the Cape Verde groups. The major splits among these groups occurred during the Late Miocene/Pliocene; ...
AimWe used published data of the floristic and elevational distribution of seed plants of Bhutan ... more AimWe used published data of the floristic and elevational distribution of seed plants of Bhutan to test the contribution of climatic, topographical and biogeographical variables to shape elevational species richness and endemism patterns.LocationBhutan.MethodsWe compiled data of seed plant species distributions from the Flora of Bhutan and related them to energy, humidity, and topographically related variables and biogeographical distributions. We used multiple regression models to identify most predictive independent variables by multi‐model‐inference based on AICc.ResultsWe find highest species richness at mid elevations (1500–2000 m), while endemic richness peaks markedly higher at 4500 m. Separated for life forms, the peak of richness shifts upward along the elevational gradient in the order of trees – shrubs – herbs – graminoids. Elevational richness peaks of temperate taxa were centred at high and of tropical taxa at low elevations. Temperature was identified as most influent...
Didymodon hengduanensis is described as a new species from the Hengduan Mountains in the province... more Didymodon hengduanensis is described as a new species from the Hengduan Mountains in the provinces of Sichuan and Yunnan, China. It is characterized mainly by its lanceolate to ovate-lanceolate and appressed-incurved leaves when dry, acute leaf apices, recurved to revolute margins, the yellowish color in KOH, percurrent to subpercurrent costa, and marginal basal cells forming a distinctly differentiated area of smooth and transversely thick-walled cells. Drawings and light microscope photographs of the new species are provided. The principal characters that separate it from the most similar species are discussed.
Ceylon Journal of Science (Biological Sciences), 2016
As part of a study initiated to trace the evolutionary relationships and biogeographic affinities... more As part of a study initiated to trace the evolutionary relationships and biogeographic affinities of Sri Lankan complex thalloid liverworts, we here present the morphological diversity of Sri Lankan complex thalloid liverworts. This serves as the first detailed taxonomic study of the group in Sri Lanka. Specimens were collected from different geographical regions covering almost all topographic and climatic zones of the country. This study revealed 9 genera of complex thalloid liverworts in Sri Lanka. Based on our collections and identifications we prepared a generic key to Sri Lankan complex thalloid liverworts. Taxonomic descriptions were prepared for all identified genera
The phylogenetic placement of Monocarpus sphaerocarpus D.J.Carr (Monocarpaceae), a member of the ... more The phylogenetic placement of Monocarpus sphaerocarpus D.J.Carr (Monocarpaceae), a member of the complex thalloid liverworts with highly specialised morphology, presumably related to its saltpan habitat, has been determined on the basis of molecular data. Within the complex thalloid liverworts, Monocarpus resolves as sister to the Sphaerocarpales clade. A new line drawing of Monocarpus is provided, as are the first colour photographs of living plants. Detailed ornamentation of the spores of Monocarpus collections from Australia and South Africa, as revealed by scanning electron micrography, is reported, and some of the morphological features that unite and separate Monocarpus and the Sphaerocarpales s.str. are discussed.
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